1. Field of the Invention
This invention relates to a method of detecting microscopic defects existing on a silicon wafer, and especially relates to a method of detecting microscopic defects existing on a silicon wafer which is effective to sensitively detect microscopic defects existing on a silicon wafer.
2. Description of the Prior Art
As the design rule of the integrated semiconductor devices shrinks smaller and smaller, it is required to further minimize the defects at the silicon wafer surfaces, such as pits, scratches, precipitation or deposition of organic, inorganic, and metal particles, especially the ones with sub .mu.m scale.
In order to achieve the above requirement, consideration to the detailed characterization of these defects is desired. Currently, the "particle counters" which employ light scattering method are widely used among silicon wafer manufacturing factories and semiconductor device manufacturing factories to detect these defects.
However, the resolution limits of the "particle counters" are some 100 nm or larger and further smaller defects, which potentially cause serious degradation of the yield for the next generation devices with further smaller design scale, cannot be detected.
There are other techniques to detect these microscopic defects or deposited species, such as the one using radio isotope methods. However, these techniques require complicated preparation procedure and special expensive set-ups.